Written by a Jeep newbie, for Jeep newbies. Owned my 2002 TJ SE for about 4 weeks, and had to replace the throttle position sensor last night. Troubleshooting is not documented here, because TPS failure modes seem to be common and are listed in about every other post here. Regardless, here it goes:
Throttle Position Sensor replacement ( pictures shown for 2.5L motor, though I did a '96 XJ Cherokee 4.0 and I believe the actual TPS is the same).
~20 minutes (do it while you're draining oil for a oil change)
1) TPS - take the advice on the forum, use an OEM Mopar part (# 4874371AC from Morris 4x4)
consumables (as necessary)
- 3-inch hose clamp x 3
- thread-lock of your choice
- throttle body/ mass air flow cleaner (or some other quick-evaporating aerosol cleaner)
- electrical contact cleaner (aerosol)
- dielectric grease
- 1/4" ratchet drive (short handle)
- 1/4" Torx bits, T20 size
- flat-blade screwdriver
- 8mm wrench or socket
Reference Point List (see photos for references):
(B) Intake Air Cleaner
(C) Intake Air Duct/Resonator Box
(D) Throttle body
(E) Throttle Cable
(F) Throttle Position Sensor (TPS)
(G) TPS wiring harness
disconnect the negative battery cable from the terminal
- go ahead and hit the terminal with a wire brush to get the crud off.
loosen the hose clamps on the air hose from the intake air cleaner box and the throttle body.
8mm wrench or screwdriver, whichever is easier.
remove the two screws holding the intake air resonator to the engine valve cover.
Use 8mm wrench.
pull the intake air ducting away from the throttle body.
Go ahead and clean the throttle cable pivot point (external to the throttle body), and clean around the throttle plate (interior of the throttle body).
locate the throttle position sensor connector and remove from the throttle position sensor.
This connector uses a small locking slider on the top of the sensor. slide it out and wiggle the connector off.
clean the contactors on the sensor connector.
give it a spray with electrical contact cleaner.
locate the throttle position sensor and remove.
there are two screws (only one shown, difficult location to photograph) that must be removed with a T20 bit. Use a ratchet/bit, or if you've got one, a snubby T20 screwdriver. it's crammed right up there next to the firewall so have a flashlight and patience.
install new throttle positon sensor.
you'll have to give it a little wiggle to line it up with the throttle plate pivot shaft, but it will slide right on. put some thread-locker on the two screws, and tighten down. careful not to crack the plastic sensor housing.
reconnect the wiring.
slide the connector back on and click into place
reinstall the air duct.
push back down onto throttle body, re-install screws holding resonator to valve cover, and reattach hose end to intake air filter box. tighten hose clamps.
finish your oil change.
finish your beer (cause you did it so fast).
congratulate yourself for having done this while teaching your toddler what all the parts of the throttle body are called.
have another beer.